Insulation for absorbing condensation in metallic structures



May 29, 1934- M. T. CHAMBERLAIN ET AL 1,960,867

INSULATION FOR ABSORBING CONDENSATION INV METALLIC STRUCTURES Filed Feb. 13, 1933 Patented May 29, 1934 UNITED STATES INSULATION FOR ABSORBING CONDENSA- T ION IN IMETALLIC STRUCTURES Martin T. Chamberlain, Joliet, and Edwin E. Mortell, Kankakee, Ill., assignors to J. W. Mortell Company, a corporation of Illinois Application February 13, 1933, Serial No. 656,618

1 Claim.

The invention relates to insulation for absorbing condensation in metallic structures, and is particularly adapted to be employed in box cars which have steel roof decking and steel Walls.

The condensation of moisture in box cars of the character described causes heavy losses to railroad companies as the Water which condenses upon the steel decking and sides under certain conditions drops upon the contents of the cars and when these contents are flour, sugar, sheet metal, meals, cement in bulk, etc., they are damaged in many instances to such an extent that the railroads must pay for the damages thereto. In explanation, it Will be readily understood that 1f a box car has been standing n a siding during cold weather until it has been thoroughly chilled and is then loaded with a substance such as our which, when it is processed, is often heated to a temperature of 90 to 140 F. or more and contains 2J a small percentage of moisture, the heat of the flour will Warm up the interior of the car and moisture will condense onvthe cold walls andceiling. When-a suilicient amount of moisture has condensed upon the walls and ceiling, drops 2 'thereof will fall upon the flour. Oftentimes the flour is damaged to such an extent that the consignee refuses to accept delivery of the shipment and the railroad company is forced to pay the claim for damage to 'the flour.

3 Box cars which embody the preferred form o the invention are insulated with a material which possesses a low co-emcient of heat conductivity and is adapted to absorb surface condensation a's rapidly as it forms. Thematerial is adapted to hold the moisture during the condensation stage and then gradually and readily releases the moisture so absorbed'to the atmosphere. However, the moisture is released by evaporation and not in the form of drops which will fall upon the contents of the car. The insulating material is preferably secured to the inner surfaces of the steel decking and sides with an adhesive having such purpose or characteristics that the insulating material adheres to the steel surfaces in cold or hot weather and in spite of any vibration due to the bumping and jarring to which all of the cars are subjected during their movement. The substance or adhesive which secures the insulating material to the metallic surfaces is preferably of such a nature that it water-proofs the surfaces that are in contact with the metal. This prevents the absorbed moisture from reaching thev surfaces of the steel decking or sides and thereby prevents the moisture from destroying the insulating value of the material and also its bond to the metallic i surface. By preference, the insulating material is not wholly absorbent as it must not allow the absorbed moisture to pass entirely through the material. Briefly, the insulating material functions as a reservoir for holding the moisture con- G0 densed upon its surface, the insulating material f being adapted to release this moisture to the atmosphere by evaporation under suitable conditions.

Other objects and advantages will become apparent as the following detailed description progresses, reference being had to the accompanying drawing, wherein:

Figure l is a vertical transverse section taken through a box car which embodies `the invention.

Figure 2 is a section taken on line 2 2 of Fig-V ure 1.

Figure 3 is ran enlarged fragmentary section taken through insulating material which embodies the invention, and

Figure 4 is a fragmentary section taken through insulating material which embodies another form of the invention, the insulating material being .shown attached to steel car decking.

Referring to the drawing, the reference character 10 designates generally the under structure of a box car which is provided with steel side walls 11 and steel roof decking 12. 'Ihe steel decking 12 is reinforced by the usual carlines 13 and purlines 14. The car is provided with the usual Wood lining l5 along the sides thereof and the usual wood lining 16 at the ends thereof. This lining acts as an insulator and reduces the amount of condensation so that very little moisture condenses on the inside surface of the Wood against which the contents of the car are placed. It will be noted that there are air spaces 17 be-` tween the steel walls of the car and the wooden linings 15 and 16. It will also be noted that in the present instance the wood linings 15 and 16 stop short of the licor of the car. y

The bottom surfaces ofthe steel decking 12, the carlines 13 and the purlines 14 are-covered with insulating material 20 which is preferably a ju'te :liber mat. This may be described as a jute felt pad.l Other materials which may be employed for this purpose are felt or wood fiber mats, hairr felt, paper, sponge, burlap, cotton cloth or similar materials Which will absorb by capillary attraction. The back surface of the mat or pad 20 is coated with a water-proofing substance which penetratesthe brous pad a sufficient distance to prevent moisture from being drawn completely through the pad by capillary at'traction. This water-proofing is in the 1'10- form of a liquid paste or a plastic .cement and may be brushed or sprayed on the pad or on the surface to which the pad is to be applied. The water-proof coating may also be applied to the pad by dipping the back side thereof into the bath of the liquid. The water-proofing agent preferably employed is emulsified asphalt. Another agent which may be employed is sodium silicate.

When emulsied asphalt is employed as the water-proofing medium, the asphalt is preferably treated in such manner that the flow point thereof is sufficiently high to prevent the asphalt from flowing in hot weather. Such flowing of the asphalt will permit the insulating pad to become loose in hot weather, especially if the car were subjected to bumping or jarring. It may be mentioned that the emulsied asphalt will not crack or peel off during cold weather.

Figure 3 illustrates the manner in which the back surface of the jute felt pad 20 isl impregnated with the emulsiiied asphalt, the emulsified asphalt being shown by stippling at 22.

After the water-proofing adhesive has been applied to the back of the mat or to the interior surface of the steel decking 12, the mat is pressed against this surface and held in this position until the combined water-proofing agent and adhesive has formed a bond between the metal and the pad.l This is effected by rollers which press the mat firmly into the adhesive and tightly and smoothly against the steel surface. On sloping car roofs, the moisture absorbed by the jute pad 20 will gravitate down through the pad toward the side walls of the car as the saturation point is approached. Strips 24 of jute felt are preferably provided along the side and edges of the pad 20 and the ends thereof to receive and absorb this moisturei f These mat `strips 24 are preferably made to adhere with the water-proof adhesive in the same manner as the pad 20. They are applied to the upper part of side and end walls down to or slightly past the upper edges of the wood linings 15 and i6. Moisture will pass from the edges of the pad 20 into the strips 24 by capillary attraction or by gravitation from the edges 'of the pad 20 down unto the upper edges of the strips 24. The strips 24 are preferably thicker than the pad 20. Thus, the pad 20 is preferably of the order of lAsth or 1%; of an inch in thickness and the strips 24 are preferably of the order of llth to l of an inch in thickness.

Strips 26 and 27 of jute felt, or the equivalent, are also provided to absorb moisture which may condense on the steel side and end walls of the car and on the wooden linings 15 and 16. The strips 26 and 27 are preferably of the same thickness as the strips 24 and are preferably made to adhere with water-proofed adhesive in the same manner as the strips 24Kand the pad 20. The strips 26 and 2'7 are applied to the lower marginal portions of the steel side, end walls and wooden linings as shown in Figures 1 and 2. It will be readily understood that any moisture which condenses on the inner surfaces of the steel side and end walls may run down along these surfaces to the strips 26 which will absorb .the moisture. Moisture which runs down along the outer surfaces of the wooden linings 15 and 16 will be absorbed by the strips 27.

Where metallic members such asbolts project lthrough the wooden linings 15 and 16 and tend to condense moisture which may drop upon the contents of the car, the inner ends of the members or bolts are also covered with insulating material of the character described above. Thus.

I have shown bolts 28 having heads which abut the inner surfaces of the wood linings 15 and 16. The heads are covered with insulating material 29 which is preferably formed of the same substance as the mat 20 and is secured to the bolts 28 by emulsied asphalt, or the equivalent.

In practice, it has been found that when car roofs are insulated in the manner described above and are used during a long, cold spell, they ac cumulate the condensation of more than one carload, and, due to freezing or other similar causes, they do not give the accumulated moisture back to the atmosphere and in timethe saturation point of the absorbent mat is approached. This throws a burden on the strips 24 so that they become supersaturated and drip. The condensed moisture runs down the wood lining and reaches the cargo below to damage the material in conta with the lining.

To overcome this condition, we provide wooden strips 30 with beveled tops. The strips 30 are preferably nailed to the wood lining just below and parallel to the bottom of the mats or strips 24. The beveled surfaces and the wood linings then form small gutters to gather the drip from the mats or strips 24. To dispose of themoisture which accumulates in the gutters, we provide holes 31 through-the wooden linings 15 and tubes 32 which project through the holes 31 and through holes 33 provided in the steel 'side walls 11. Obviously, moisture which collects in the gutters formed by the strips 30 will be discharged to the outer side of the steel side walls 11.

It will be noted vthat the wood linings 15 are secured to the steel side walls 1l by the bolts 28 which project through nailing strips 34. These nailing strips are cut away intermediate the bolts 28 as indicated at 34a. Insome instances, the. tubes 32 and .the-holes 33 will befomitted so that moisture accumulating in the gutters will drain through the holes 31 down along the outer sides of the wooden linings 15 to be absorbed in the strips 2'7.

The improved insulation for absorbing moistur which condenses thereon is preferably adapted to absorb two or more times its Weight in moisture and to hold this moisture until it evaporates. The purpose of this construction is as follows: If it is assumed that a car which has been subjected to minus 10 F. is loaded with flour inthe temperature of F. and the our has a temperature of 120 F., the heated-flour, with its moisture content, will evaporate approximately 2 or 3 gallons of water if the car is again subjected to cold weather for several days. 'I'his evaporation will continue until the flour cools off to a sufficient moisture content, which was absorbed immediately and frozen in the insulation and remained therein until another hot load of flour was placed in the car, the second' quantity of moisture evaporated from the 'our would be absorbed by ythe roof insulation. Generally, the thickness of the roof insulation is such that several consecutive lots of flour, or vthe equivalent, may be handled and the moisture evaporated therefrom will be absorbed by the roofingv insulation without any appreciable evaporation between several loadings.

It is of much importance to railroad companies that the preferred embodiments of the invention do not absorb odors and therefore prevent the contents of 4the car `from beingl subjected to the odors of a previous load. Neither are the pads or strips loosened or destroyed when it is cleaned of dust by blowing with compressed air; a practice of cleaning out box cars common with railroad companies.

It will be readily understood that if it is so desired, the insulating material may be backed with a Water-proof compound'and secured to the metallic surfaces by another compound. Thus, the insulating material may have its back surface impregnated with emulsied asphalt, oir theequivalent to waterproof it and some suitable adhesive may be employed to secure the waterproofed surface to the metallic surface.

Another novel feature of this invention is that owing to thelow factor of heat conductivity of the insulating mat and the adhesive, the temperature .at which condensation will form is considerably lower than in the case of the plain exposed steel roof surfaces. Y

Another form of the invention is illustrated in 4 Fig. 4 in which steel roofdecking for a box car is shown at 12a. A layer of adhesive 35, which preferably comprises emulsifled asphalt, is rst applied to the inner surface of the roof decking 12a. Loose fibers are then blown or sprayed or otherwise applied to the adhesive until a relatively thick 'coating of the fibers has been formed as indicated at 36. The brous coating 36 functions in the same manner as the mat or pad 20 described above.

While we have .shown and described certain embodiments of our invention, it is to be understood that it is capable`of many modifications. Changes, therefore in the construction and arrangement may be made without departing from the spirit and scope of the invention as disclosed in the appended claim, in which'it is our intention to claim all novelty inherent in our invention as broadly as possible, in view of the prior art.

We claim:

In a box ycar having metallic roofing and metallic side walls, wooden linings extending parallel to and spaced from said side walls, a layer of absorbent material secured to the inner side of said roong, strips of absorbent material disposed along the lower edges of said side walls and strips of absorbent material disposed along the lower edges ofsaid wooden linings.

MARTIN rr. CHAMBERLAIN. EDWINVE. MORTELL. 

